A twin-type sunlight-shielding device structured in such a way that a top shielding material and bottom shielding material installed above and below an intermediate rail are switched and moved up and down by operating a single-loop up/down operation cord has heretofore been known (refer to Patent Literature 1).
In addition, a structure whereby double sunlight-shielding materials, one on the interior side and the other on the exterior side, can be pulled up independently using a single operation cord is known, wherein such structure has: a first clutch unit that allows for selection of pulling up the first sunlight-shielding material, letting it drop due to its dead weight, or preventing it from dropping due to its dead weight, by operating the operation cord in one direction; and a second clutch unit that allows for selection of pulling up the second sunlight-shielding material, letting it drop due to its dead weight, or preventing it from dropping due to its dead weight, by operating the operation cord in the other direction (refer to Patent Literature 2).